Suitability of Biosilicate® glass-ceramic powder for additive manufacturing of highly porous scaffolds

The Biosilicate (R) glass-ceramic is one of the most promising alternatives to the 45S5 Bioglass (R) in terms of bioactivity, osteoconductivity, osteoinductivity, non-cytotoxicity, and antibacterial properties, with significant advantages in the manufacturing of specific components of complex shapes for bone tissue application. Unlike in 45S5 glass, the crystallization does not lead to a degradation of bioactivity. In the present paper, we explored the suitability of Biosilicate (R) for the manufacturing of highly porous scaffolds (porosity of 50-80 vol%) by using modern additive manufacturing technologies, such as direct ink writing (DIW) and digital light processing (DLP). Both techniques could be easily applied to fine powders of Biosilicate (R) mixed with fugitive binders. Significant densification of the struts, despite the limited powder packing, could be achieved using liquid-assisted sintering, in turn, triggered by the phosphate-enriched residual glass phase, already at 1000 degrees C. The strength-to-density ratio could be variously tuned (from 1.5 to 9.5 MPa cm(3)/g), especially with DLP-derived samples, by adjusting both the firing temperature and the scaffold topology.